Cell is the Greatest Threat to Gohan in Dragon Ball Z.
This understanding continues to deepen as we witness Cell’s reaction to Gohan’s new Beast form, which he first showcases in Dragon Ball: Sparking! Zero.
Dragon Ball Super: Super Hero has elevated Gohan back to the level of Goku and Vegeta in a new battle against a revamped version of Cell. The film has brought Gohan to a point he has never reached before, leading to a drastic transformation that is entirely unprecedented for him. Gohan Beast also possesses tremendous power, akin to the latest forms of Goku and Vegeta.

This Marks a Pivotal Moment for Gohan, Similar to His First Battle Against Cell in the Cell Saga of Dragon Ball Z.
Gohan has utilized his latent potential to create a significant transformation that completely overwhelms Cell. However, Dragon Ball: Sparking! Zero has taken this notion even further by revealing how Perfect Cell will react upon witnessing Gohan Beast in action.
Gohan is significantly stronger than Cell when he is in Super Saiyan 2 form, and currently, he appears even more formidable. It is clear that Cell is not yet ready for a rematch.
In the manga, Dragon Ball Super provides additional material to conclude the events of Dragon Ball Super: Super Hero, and the author has released more detailed information about Gohan Beast. Gohan explains that this transformation is a result of him tapping into his latent potential just before losing control. When unleashing this power, Goku and Vegeta realize that this form is on par with Goku’s Ultra Instinct and might even rival Broly’s Super Saiyan strength when all their powers are fully unleashed.